which the spectrophotometric method fails. It gives equivalent results. NN′-Dimethylthiourea displaces heterocyclic leaving groups at rates similar to those for piperidine. Compared with α-hydrogen, α-methyl groups render pyridine a less effective leaving group, whereas α-ethoxycarbonyl groups show a large rate enhancement.
开发了一种电导法以获得分光光度法失败的标题反应的速率。它给出了等效的结果。NN “-Dimethylthiourea取代以类似于那些
哌啶率杂环离去基团。与α-氢相比,α-甲基使
吡啶成为较低效的离去基团,而α-乙氧羰基则显示出较大的速率增强。